Wellbores may be drilled to locate and produce hydrocarbons, minerals, or water. The drill string and the downhole tool are typically composed of a series of pipes threadably connected together to form a long tube with a drill bit at the lower end thereof. As the drilling tool is advanced, drilling mud is pumped from a surface mud pit through a passage or passages in the drilling tool and out the drill bit. The mud exiting the drill bit flows back to the surface to be returned to the mud pit and may be re-circulated through the drilling tool. In this manner, the drilling mud cools the drilling tool, carries cuttings and other debris away from the drilling tool, and deposits the cuttings and other debris in the mud pit. As is known, in addition to the cooling and cleaning operations performed by the mud pumped into the wellbore, the mud forms a mudcake that lines the wellbore which, among other functions, reduces friction between the drill string and subterranean formations.
During drilling operations, communications between the bottom hole assembly (which may include a plurality of components) and a surface-based processing unit and/or other surface devices may be performed using a telemetry system. In general, such telemetry systems enable the conveyance of power, data, commands, and/or any other signals or information between the bottom hole assembly and the surface devices. Thus, the telemetry systems enable, for example, data related to the conditions of the wellbore and/or the bottom hole assembly to be conveyed to the surface devices for further processing, display, etc. and also enable the operations of the bottom hole assembly to be controlled via commands and/or other information sent from the surface device(s) to the bottom hole assembly.
Various wellbore telemetry systems may be used to establish the desired communications capabilities. Examples of such systems may include a mud pulse telemetry system as described in U.S. Pat. No. 5,517,464, a wired drill pipe wellbore telemetry system as described in U.S. Pat. No. 6,641,434, an electromagnetic wellbore telemetry system as described in U.S. Pat. No. 5,624,051, an acoustic wellbore telemetry system as described in PCT Patent Application No. WO2004085796, all of which are incorporated by reference herein in their entireties. Further examples using data conveyance or communication devices (e.g., transceivers coupled to sensors) have also been used to convey power and/or data between a bottom hole assembly and a surface unit.
Telemetry systems typically involve transmitting data captured by a bottom hole assembly (e.g., one or more components composing a bottom hole assembly) to a surface system or unit. With these systems, data is typically collected and organized in packets, which may be referred to as frames, containing one data point or multiple data points. The data is typically transmitted uphole in a constant or continuous data stream. For example, a set of data collected from individual components is gathered into frames and conveyed to the surface. Data from a frame is continuously sent to the surface until all of the data from that frame has been sent. A series of frames containing interleaved data from various components is typically sent uphole to the surface. The above-described process is repeated for a given set of frames and/or may be repeated continuously (e.g., until power is turned off). Telemetry components or systems typically have practical limitations (e.g., bandwidth) that restrict the data rate and/or the amount of data that can be transmitted uphole in a given time period. As a result, there are often delays sending data from the bottom hole assembly to the surface and/or receiving data at the surface. Additionally, repeated data often consumes the limited available telemetry bandwidth, thereby slowing or preventing the transmission of data relating to key information and/or important events.